-LRB- CNN -RRB- -- The crane operator facing charges over a deadly building collapse was denied bail Sunday .

A Philadelphia judge refused to allow Sean Benschop , 42 , to leave jail .

He is charged with six counts of involuntary manslaughter , 13 counts of recklessly endangering another person , and one count of `` risking a catastrophe , '' District Attorney spokeswoman Tasha Jamerson told CNN .

Wednesday 's building collapse in downtown Philadelphia left six dead and 13 people injured .

Benschop , who maintains his innocence , turned himself in Saturday .

`` My client is being made the scapegoat in this situation , '' said Daine Grey , Benschop 's attorney .

`` The victims here are n't just those who died and their families . My client is a victim as well . He 's currently being looked at as the cause of everybody 's pain , but that just is n't the case . ''

Grey told reporters Saturday that while his client feels `` extremely sympathetic and remorseful , '' he is not guilty .

`` This was an accident , but Mr. Benschop was not responsible , '' Grey said , in remarks captured by CNN affiliate WPVI . `` And we believe that , in time , the facts will show that he is not responsible . ''

Benschop had marijuana and pain medication in his blood after the collapse , a law enforcement source told CNN .

Pennsylvania court records indicate Benschop , who also went by the alias Kary Roberts , has been arrested multiple times in the past two decades . Many of the related charges -- related to alleged firearms violations and theft -- were withdrawn , dismissed or resulted in not guilty verdicts , though he was found guilty in the mid-1990s on drug charges .

Philadelphia Mayor Michael Nutter blamed Benschop 's `` reckless and irresponsible behavior '' for the building collapse and said Saturday he hopes that Benschop faces `` the harshest level of charges ... and he is punished accordingly . ''

`` Justice will only be served if Sean Benschop receives a sentence that buries him in a jailhouse forever , just like his victims were buried on Wednesday , '' Nutter said .

Nutter is pressing for answers from two property owners who hired Benschop to operate heavy machinery , saying that , along with Benschop , they `` bear the ultimate and sole responsibility for this tragedy . ''

Benschop allegedly was working a crane to tear down a vacant building in downtown Philadelphia when a four-story wall collapsed onto a Salvation Army thrift store , causing an ominous rumble followed by panic on the streets .

Afterward , searchers climbed over shards of wood , concrete and rebar looking for survivors , such as a 61-year-old woman pulled alive from the rubble early Thursday .

The first lawsuit against him was filed that same day , by attorneys for a 54-year-old woman pulled from the rubble by a firefighter .

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NEW : Attorney for crane operator says his client is `` being made the scapegoat ''

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Sean Benschop was denied bail Sunday

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A law enforcement source says marijuana was found in the crane operator 's blood

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6 died , 13 were injured when a building being torn down collapsed onto a thrift store